Spectroscopy. IR spectroscopy, DSC, TGA
Spectroscopy and thermal analysis techniques, such as UV-VIS, FTIR, DSC, TGA, are complementary to X-ray diffraction phase and structure analysis, expanding possibilities for correct crystal structure solution and refinement, along with correct determination of phase compositions for complex mixtures.
UV-VIS spectroscopy is a method intended for measurement of optical absorbance and reflectance of the substances within the wavelength range of 250 – 1100 nm (from medium ultraviolet to near infrared region). UV-VIS spectroscopy can provide information on oxidation state of elements constituting the sample, their first-shell coordination features. The method of diffuse scattering (diffuse reflectance) is especially useful for study of nanocrystalline powders such as oxide-based semiconductors and catalysts.
FTIR spectroscopy is a mandatory technique in the materials science. Depending on the method used, the spectral data can be collected within the wavelength range of 380 – 11000 cm-1. The obtained information is useful for understanding chemical composition of the substance, including presence and chemical state of water and different kinds of functional groups in organic and inorganic substances.
Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) are useful for correct interpretation of the data obtained in the course of non-ambient X-ray diffraction studies. The Netzsch STA 449 F3 calorimeter allows determination of melting and solidification points of the substances, weight loss, temperature ranges of phase transitions; it can be applied for calculation of thermal effects of reactions and transitions that can occur during heating/cooling of studied substances.
- Sergei Britvin The Leading Researcher in spectroscopic, chromatographic and thermal methods